st: Kappa and combining intra and inter rater readings

[Garry Anderson <g.anderson@unimelb.edu.au>]

I have 150 radiographs that have been measured by 4 raters, each rater 
making two measurements. The outcome in binary.

I was wishing to summarise inter rater agreement and one way to do this on 
the first readings is
-kap rater11 rater21 rater31 rater41-

Alternatively one could use the only the second reading
-kap rater12 rater22 rater32 rater42-

Other combinations of first or second reading for each rater could be done 
to maximise use of the data.

Is -kap- able to combine these combinations so as to obtain an estimate and 
confidence interval of inter rater kappa?
Can -kap- be used to obtain an overall estimate of kappa for intra rater 
agreement?

Summarising kappa in this way would lose the fine structure, but that may 
be appropriate if individual kappas are similar.

Kind regards, Garry


The -kap obs1 obs2- command 
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